SOIL CHEMICAL PROPERTY CHANGES ON GOLF COURSE FAIRWAYS UNDER EIGHT YEARS OF EFFLUENT WATER IRRIGATION

摘要

Effluent water used for landscape irrigation has the potential to change soil chemical properties over time.Changes in soil chemistry can be observed across a range of time scales and in a variety of soil conditions.The objective of this study was to determine long-term changes in soil chemistry in soils under effluent water irrigation on golf course fairways.Soil testing was conducted for the years of 1999,2000,2002,2003,and 2009 for Heritage Golf Course in Westminster,Colorado.Parameters of each soil sample tested included pH,extractable salt content (calcium,magnesium,potassium,sodium,iron,manganese,copper,zinc,phosphorus,and boron),base saturation percent of calcium,magnesium,potassium and sodium,soil organic matter (SOM),and cation exchange capacity (CEC).Regression analysis was used to evaluate the changes in individual soil parameters over time after the use of effluent water for irrigation.Soil pH,CEC,extractable aluminum,copper,manganese and iron along with both base saturation percentages and exchangeable percentages of calcium and magnesium did not change over time.The strongest indications of change are seen for extractable boron (R2 = 0.56),Bray II extracted phosphate (R2 = 0.56),and sodium base saturation percentage (R2 = 0.44).The regression analysis indicated that B,P,and sodium increased linearly during the 8 year’s irrigation with effluent water.Further studies are needed to determine if these parameters would continue to increase or would stabilize.Continued accumulation of sodium could eventually result in loss of soil structure.